Ok so my battery died yesterday and I replaced the stock acdelco with an optima

. I hadnt realized until after I bought it that its the largest yellow top they have

. Started like a champ after I let the engine run for a bit. Its a deisel battery, pricy too but I didnt front the cash

. 870 Crank Amps

. Since its deep cycle it will be nice for audio stuff, and its nice it has 2 sets of terminals(Gm and Top accesories).
This got me to thinking about just upgrading the parts that I can install myself with a bit of help and luck. What do you guys reccomend thats cheap and effective. I know nill about this stuff. Iridium sparkplugs? Cold air intake etc. What will give the car back the power that I felt when I first drove it?

Its the 3400 engine.
Im not gunna race it but I wanted to give it more juice just for fun. So I dont think Ill drop half the cost of the car on a supercharger

.
Thanks
